Thanks Fred, Susan and John for your replies. I guess the takeaway is to think of this solely as a process of mineralization and that rate of fossilization is variable and dependent upon many environmental conditions.

All the best!
Bob

> On Jan 4, 2014, at 5:30 PM, Fred Schueler <[log in to unmask]> wrote:
>
>> On 1/4/2014 8:15 PM, Ed and Susan wrote:
>> There is really no set way of defining the term “subfossil”.
>
>> There is no real definition, but I might stick my neck out and say that
>> “subfossil” seashells would have to be at least a thousand years old
>> (rather than ten years or a few hundred years.)
>
> * "fossil" originally means "dug up" so the term references how the
> specimen was found, not necessarily its condition or age. Any remains
> that have been buried in substrate are fossils in terms of the original
> definition. One way of defining the difference between "proper fossil"
> and "subfossil" would be the state of the substrate - if it's still not
> different from surface or currently-reworked soil/sediment, then
> subfossil, if modified by mineralization/compression, then a proper fossil.
>
> fred.
> ------------------------------------------------------------
>         Frederick W. Schueler & Aleta Karstad
> Mudpuppy Night in Oxford Mills - http://pinicola.ca/mudpup1.htm
> Daily Paintings - http://karstaddailypaintings.blogspot.com/
>         RR#2 Bishops Mills, Ontario, Canada K0G 1T0
>  on the Smiths Falls Limestone Plain 44* 52'N 75* 42'W
>   (613)258-3107 <bckcdb at istar.ca> http://pinicola.ca/
> The 2014 Bishops Mills Calendar Festival:
> Fred:
> http://karstaddailypaintings.blogspot.ca/2013/12/the-fred-calendar-for-2014.html
> - data input
> Aleta: http://www.lulu.com/content/14204755 - paintings
> Jennifer:
> http://www.zazzle.com/free_range_wall_calendar-158319768903951661  -
> free ranging livestock
> Rory: [watch this space for the revolutionary calendar]
> ------------------------------------------------------------
>
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